pub struct SubclassedWndProc {
	old_wnd_proc: WNDPROC,
	config: Config
}

impl SubclassedWndProc {
	pub fn new(config: &Config) { //-> Self {
		let mut new_proc = SubclassedWndProc{ old_wnd_proc: None, config: *config };

		// Subclasses window and gets the old WndProc function location in memory
		let proc_location = unsafe { SetWindowLongA(&mut *config.h_hammer_hwnd, GWL_WNDPROC, wnd_proc as i32) } as isize;

		// convert old wndproc memory location to function pointer
		let old_wnd_proc = unsafe {
			mem::transmute::<isize, unsafe extern "system" fn(HWND, u32, usize, isize) -> LRESULT>(proc_location)
		};
		new_proc.old_wnd_proc = Some(old_wnd_proc);

		unsafe { G_SUBCLASSED_PROXY = mem::transmute::<Mutex<SubclassedWndProc>, G_SUBCLASSED_PROXY>(Mutex::new(new_proc)) };
		// G_SUBCLASSED_PROXY.set_value(new_proc);
		// new_proc
	}
}

#[no_mangle]
#[allow(private_no_mangle_fns)]
unsafe extern "system" fn wnd_proc(hwnd: HWND, message: u32, w_param: WPARAM, l_param: LPARAM) -> LRESULT {
	match message {
	    // do stuff here
	}
	CallWindowProcA(G_SUBCLASSED_PROXY.lock().unwrap().old_wnd_proc, hwnd, message, w_param, l_param)
}

lazy_static! {
	pub static ref G_SUBCLASSED_PROXY: Mutex<SubclassedWndProc> = Mutex::new(SubclassedWndProc {
		old_wnd_proc: None,
		config: Config::default()
	});
}